Hydrodynamic Transport Coefficients in Relativistic Scalar Field Theory

Hydrodynamic transport coefficients may be evaluated from first principles in a weakly coupled scalar field theory at arbitrary temperature. In a theory with cubic and quartic interactions, the infinite class of diagrams which contribute to the leading weak coupling behavior are identified and summed. The resulting expression may be reduced to a single linear integral equation, which is shown to be identical to the corresponding result obtained from a linearized Boltzmann equation describing effective thermal excitations with temperature dependent masses and scattering amplitudes. The effective Boltzmann equation is valid even at very high temperature where the thermal lifetime and mean free path are short compared to the Compton wavelength of the fundamental particles. Numerical results for the shear and the bulk viscosities are presented.Comment: 116 pages. An error in printing the figures file is corrected. The bulk viscosity sections are corrected and entirely rewritten. 38 figures in post-script format. One style file is include

Diabetic gastroparesis: Therapeutic options

Gastroparesis is a condition characterized by delayed gastric emptying and the most common known underlying cause is diabetes mellitus. Symptoms include nausea, vomiting, abdominal fullness, and early satiety, which impact to varying degrees on the patient’s quality of life. Symptoms and deficits do not necessarily relate to each other, hence despite significant abnormalities in gastric emptying, some individuals have only minimal symptoms and, conversely, severe symptoms do not always relate to measures of gastric emptying. Prokinetic agents such as metoclopramide, domperidone, and erythromycin enhance gastric motility and have remained the mainstay of treatment for several decades, despite unwanted side effects and numerous drug interactions. Mechanical therapies such as endoscopic pyloric botulinum toxin injection, gastric electrical stimulation, and gastrostomy or jejunostomy are used in intractable diabetic gastroparesis (DG), refractory to prokinetic therapies. Mitemcinal and TZP-101 are novel investigational motilin receptor and ghrelin agonists, respectively, and show promise in the treatment of DG. The aim of this review is to provide an update on prokinetic and mechanical therapies in the treatment of DG

A New Family of Spiders of the Sub-order Hypochilomorphae

tablished by Petrunkevitch in 1933 to include those spiders with diaxial chelicerae which also possessed four lung books. Three species are known viz. Hypochilus thorelli Marx, from North America, Ectatosticta davidi Simon, from Tibet, and Ectatosticta troglodytes (Higg. and Pet.), from Tasmania, which are all included in the family Hypochilidae. The establish-ment of this sub-order has not met with general agreement among present-day arach-nolo gists, many of whom still grol!-P these spiders with the two-lunged cribellate spiders. The occurrence of the two species recorded in the present paper, which do not possess a: cribellum seems to strengthen Petrunkevitch's case for the separation of these spiders into a separate sub-order. The three previously known species share many characters in common. They are'long-legged, sedentary spiders which construct ex-tensive webs. They possess relatively small, vertical chelicerae and the poison glands do not extend into the cephalothorax. The gen-ital bulb of the male is terminal, the heart is supplied with four pairs of ostia and they all possess a cribellum. The two species described below although they possess diaxial chelicerae, two pairs of lung books and four pairs of ostia, differ considerably in other characters from pre-viously known species. In general appearance and habit they resemble lycosid spiders. They are vagrant in habit, hunting their prey on th